Electric switch mechanism including a permanent terminal assembly and a complemental removable snap action toggle switch unit



1966 J. J. COOPER, JR

ELECTRIC SWITCH MECHANISM INCLUDING A PERMANENT TERMINAL ASSEMBLY AND A COMPLEMENTAL REMOVABLE SNAP ACTION TOGGLE SWITCH UNIT Filed Jan 27, 1964 IAIVEAITOR: JHMES J CooPE/qJQ.

#16 QTTOAN Y United States Patent ELECTRIC SWITCH MECHANISM INCLUDING A PERMANENT TERMINAL ASSEMBLY AND A CIIMPLEMENTAL REMOVABLE SNAP ACTION TUGGLE SWITCH UNIT James J. Cooper, Jr., 4069 Wilmington Ave, St. Louis 16, Mo. Filed Jan. 27, 1964, Ser. No. 340,129 1 Claim. (Cl. MIG-51) The present invention relates in general to improvements with respect to manually operable electric switches. More particularly, the invention is directed to improvements in switch mechanisms of the snap switch type. Switches of the type under consideration are usually mounted on the walls of dwellings, buildings, and the like, although it is to be understood that the instant invention is not limited to such installations.

As is well known and understood, in present-day residences, offices, and so on, each room has at least one snap action toggle switch for controlling the lighting, such switch being usually mounted on a wall. In consequence of repeated use, malfunctioning of these switches occurs regularly, as is understood. There are of course many reasons why this is so, the most frequent one being a resultant weakness which from repeated usage develops in the spring that effects the on and off action of the contact toggle element. Breakage of parts and wear of them may also contribute to eventual inoperability of these switches. At any rate, it is common knowledge that electric snap switches frequently require replacement.

To most people, the removal of a malfunctioning wall switch and replacement thereof with a new one has posed many problems. Inherently afraid of the effects of elec trical current, the first precautionary step usually taken would be to pull or disconnect the electrical circuit main switch, often located remotely from the locale of the defective wall switch. Disconnection of the main switch, of course, immediately renders all outlets of the circuit dead, so that electric clocks cease operation, radios and television sets become inoperative, and all lighting ceases, as is well understood.

Assuming that a replacement switch is at hand, that the usual cover plate had been removed, and that the mounting screws had been withdrawn, the defective switch would be manually pulled out from its outlet box, seated in a wall socket or opening, until the terminals were in view. This last operation is rather diflicult, particularly when the wires secured to the terminals are not flexible, and this is usually the case, as is understood. Thereupon, the terminal screws would be retracted by means of a screwdriver, whereupon the exposed ends of the circuit wires could be removed from the terminal screws of the defective switch mechanism.

The next chore confronting the householder would be the securement of the exposed ends of the circuit wires to the terminals of the new switch mechanism, followed by the sometimes also vexatious operation of properly positioning and mounting the new switch mechanism. The cover plate would be replaced, and then of course the main switch of the wiring circuit would be manipulated to its on position.

The primary object of the present invention is to provide a novel and improved switch mechanism adapted to overcome and obviate most of the difficulties aforesaid. To this end, the present invention is directed to a switch mechanism that comprises two independent but cooperating units, these being a permanent terminal assembly interpolated in a wiring circuit, and a snap switch unit that may be inserted, removed, and replaced without so much as disturbing the permanent terminal assembly, or being concerned therewith.

It will of course be appreciated that a permanent terminal assembly as herein contemplated, does require initial installation. That is to say, the terminal assembly of the instant invention is principally designed for incorporation by the electrician, in wiring circuits of new building construction.

Primarily therefore, the instant inventive concept is directed to a novel switch mechanism of the character under consideration wherein, once the terminal assembly installation has been made as hereinabove indicated, a defective snap switch unit may subsequently be removed and replaced by a new one in consequence of simply removing the ordinary cover plate. In other words, any attention to or manipulation with respect to the terminals and wiring of the electrical circuit would not be necessary.

The present invention is illustrated on a sheet of drawings that accompanies this specification, and a more comprehensive understanding of its inherent features and advantages may be had from the detailed description that follows with reference to said drawings. It will be understood whenever employed hereinafter, that terms such as left, right, upper, lower, vertical and so on, have reference to parts as viewed in the drawings, and have been adopted in the interest of descriptive clarity only. In other words, inasmuch as the switch mechanism of the present invention will operate irrespective of the vertical, horizontal, or angular disposition thereof, the above noted and any directional terms employed hereinafter are not to be considered in a limiting sense.

In said drawings:

FIGURE 1 is a front elevational view of a snap switch installation embodying the mechanism of the present in- Vention;

FIGURE 2 is an enlarged vertical sectional view taken on the line 2-2 of FIGURE 1;

FIGURE 3 is a vertical sectional view taken on the line 3-3 of FIGURE 2;

FIGURE 4 is a perspective view partly in section, of the principal mechanism comprising the present invention;

FIGURE 5 is an enlarged sectional view taken substantially along the line 5-5 of FIGURE 4;

FIGURE 6 is a front elevational view of the removable snap action toggle switch unit of the invention, some of the elements thereof being omitted in the interest of illustrative clarity;

FIGURE 7 is a top plan view of said switch unit on a reduced scale;

FIGURE 8 is a front elevational view of the removable switch unit in its entirety, the scale of this view corresponding to that of FIGURE 7; and

FIGURE 9 is a front elevational view of the terminal block included in the permanent terminal assembly, and the supporting strap therefor.

As hereinbefore indicated, the present invention is comprised of two units or assemblies that incorporate an organization of elements which cooperate to form the complete switch mechanism. The first of these Wlll be termed the permanent terminal assembly, and is generally designated by the numeral It).

The assembly 10 includes a conventional rectangular outlet box 12 that is permanently seated in a surrounding opening 0 provided therefor in a wall W or the like. It is open at the front, and is defined by a rear wall 14, a top wall 16, a bottom wall 18, a left side wall 20, and a right side wall 22. Along the vertical centerline of the outlet box 12, the upper wall 16 and lower wall 18 are each provided with an integral inturned tab segment 24. These tab segments are in alignment, and as shown particularly in FIGURE 2, each of them is provided with a threaded opening 26. A pair of opposed circular openings 28 is formed in the side walls and 22, as best seen in FIGURE 5.

The terminal assembly 10 also includes the block and strap arrangement 30 shown in FIGURE 9, that is comprised of a mounting strap 32 and a block of electrically non-conductive, preferably plastic material designated as a whole by the nummeral 34. As seen to best advantage in FIGURE 2, the strap 32 includes a channel-shaped main body portion 36 that merges at the front into a pair of vertical flanges each designated 38. The block 34 is rigidly secured to and dependently supported from the upper leg segment 40 of the strap main body portion 36 by means of a relatively heavy screw 42 as shown. The lower leg segment of the strap main body portion is designated 44, and each flange 38 has formed therein a circular opening 46 and a tapped hole 43.

The block 34 is molded to provide a generally rectangular main body 50 having a pair of spaced rib formations 52 extending upwardly therefrom, and a pair of spaced rib formations 54 depending therefrom. With respect to the rib formations 52, these are adapted to lie contiguously parallel to the side edges of the strap segment 40, whereby to stabilize the block 34. The purpose of the depending rib formations 54 will be explained here inafter.

The block 34 has formed therein a pair of spaced recesses or cavities 56 of the configuration shown particularly in FIGURES 3, 5, and 9. The cavities 56 extend upwardly in the main body 50 of the block from the bottom face 58 thereof, and each includes an access portion 60 that extends rearwardly from the front face 61 of the block.

Fixed in each cavity 56, is one of a pair of spaced terminal contact elements 62. These contact elements are fabricated of resilient conductive strip material, the configuration of them being best seen in FIGURE 5. Each contact element 62 includes a hairpin-like central segment 64 that opens forwardly in alignment with the adjacent access portion 60 of a cavity 56. Each contact element 62 also includes a segment 66 that extends slightly beyond the block, and is tapped to receive the threaded shank of a conventional terminal screw 68, said screw shank engaging also in the block 34 as shown.

As noted hereinbefore, the block 34 and the described parts that are associated therewith, would be suspended from the upper leg segment 40 of the strap main body portion 36 by means of the screw 42, with the rib formations 52 lying contiguously parallel to the side edges of said leg segment. be secured to the inturned tab segments 24 of the outlet box 12, by means of screws 70 that pass through the openings 46 into engagement with the threaded openings 26.

From the foregoing, it should be apparent that the invention provides a compact self-contained terminal assembly 10. The assembly 10 is designed for permanence following its initial installation as hereinbefore indicated, and as will be explained in more detail below.

Thus, an exemplary installation is shown in FIGURE 2, where the assembly 10 is seen mounted in the surrounding opening 0 of a wall W. Prior to mounting the outlet box 12 in said opening 0, the exposed ends E of the circuit wires would of course have been brought through the openings 28 of the outlet box side walls, and rigidly secured via the screws 68 to the projecting segments 66 of the terminal contact elements 62.

The removable switch unit that is complemental to the terminals assembly 10 is illustrated per se in FIGURES 6 through 8, and is designated as a whole by the numeral 72. The unit 72 is generally of rectangular configuration, and comprises a hollow housing 74 made of nonconductive preferably plastic material, plus the elements supported thereby to be described.

The housing '74 is open at the front and includes a top wall '76, a bottom Wall 78, a left side wall 80, a right side The strap member 32 in turn, would r wall 82, and a rear wall 84. Centrally, near the open front end of the housing, the top wall 76 has formed therein a depending lug segment 86 that is opposite to an upstanding lug segment 88 formed in the bottom wall '73. The top wall 76 rigidly mounts a pair of contact elements 90. These contact elements are spaced in accordance with the spacing of the access openings 60 that lead to the cavities 56 of the terminal block 34-. The contact elements 90 are fabricated of resilient conductive strip material, and each includes a finger section 92 that projects above the housing 74, and a U-shaped blade section 94 that projects into the housing. Preferably as suggested in FIGURE 6, the housing top wall '76 is thickened in the region about the contact elements 90. The bottom wall 78 is provided with a pair of spaced depending guide ribs 96 that extend from the front to the rear end of the housing.

Appropriate means are embodied in the housing 74 for selectively establishing or breaking a connection between the two blade sections 94. To this end, the side walls and 82 have each formed therein an inwardly projecting rib section 98 that terminates short of the front end of the housing in a V-shaped notch formation designated 100. Numeral 102 designates a bridge member of conductive material that, as seen to best advantage in FIGURE 6, has a width slightly greater than the normal distance between the free extremities of the U-shaped contact blade sections 94. A manual lever 104 having a pair of wings 106 is pivotally mounted on a transverse pin 108 that has its ends fixed in the side walls 80 and 82. A lug 110 integral therewith projects rearwardly from the lever 104, and a lug 112 integral therewith projects forwardly from the bridge member 102 and toward the lug 110. The bridge member 102 includes a pair of leg segments 114 which terminate in out-turned extremities that are disposed in the V-shaped formations 100. A coil compression spring 116, interposed between the lug 110 and the lug 112, serves to maintain the leg extremities of the bridge member seated in the notches 100 when the lever 104 is manipulated through an arc adapted to move the member 102 into and out of bridging connection with the contact blade sections 94. The arcuate movements of the lever 104 are limited by the lug segments 86 and 88. This type of snap action structure is well understood in the art, and the present invention lays no claim thereto. It is noted, however, that the provision of the contact elements and the guide ribs 96 is within the concept of the present invention.

Inasmuch as the switch unit 72 is designed for cooperation with the terminal assembly 10, and actually comprises a separate unit that may readily be inserted into and removed from the permanent terminal assembly 10, a comparison of FIGURES 3, 6, and 9 is invited at this point.

It should be noted first of all, that the distance between the bottom surface 58 of the terminal block 34 and the top surface of the supporting strap leg segment 44 is minutely larger than the distance between the top surface of the wall 76, and the bottom surface of the wall 78 of the housing 74. It should also be noted that the distance between the inner faces of the terminal block depending rib formations 54 is slightly greater than the distance between the outer surfaces of the side walls 80 and 82 of said housing. It should furthermore be noted that the distance between the inner surfaces of the guide ribs 96 that depend from the housing 74- is slightly greater than that between the side edges of the leg segment 44 aforesaid.

Inview of the foregoing, it is believed abundantly clear that replacement of a worn or malfunctioning unit 72 would be an easy operation. During insertion of the unit 72, the rib formations 54 serve as guide means for the upper portion of the housing 74, whereas the rib forma tions 96 serve as guide means for the lower portion of said housing. The contact finger sections 92 are spaced in accordance with the spacing of the access portions 60 of the cavities 58 and the therein disposed central hairpinlike segments 64 of the contact elements 62. Thus it is believed clearly apparent that there can be no problem whatever when a new switch unit is being inserted.

It is also noted that the rear wall segment 36 of the supporting strap main body portion serves to limit rearward movement of a switch unit 72, so that it comes to rest with the contact fingers 92 in firm engagement with the segments 64 of the resilient terminal contacts 62.

With this arrangement, it should be apparent that the unit 72 will be removably retained in position within the channel-shaped main body portion of the strap 32 between the bottom surface 58 of the terminal block 34, and the top surface of the leg segment 44.

Normally of course, the wall opening 0 and the entire switch mechanism with the exception of the lever 104, would be shielded from view by means of a cover plate. An appropriate cover plate is shown in the drawings, being identified by the numeral 118. The cover plate 118 has a rectangular opening 120 through which the lever 104 projects, and is secured in place by a pair of screws 122 that engage in the tapped holes 48 of the strap member. In FIGURE 2, the removal of the cover plate is suggested by means of broken lines. Also suggested in this view by means of broken lines and the twodirectional arrow a, are the removal of -a worn switch unit 72, and the insertion of a new unit.

In view of the foregoing description and the drawings, it is believed that an adequate presentation for a comprehensive understanding of my invention has been given. Obviously, modification of some of the illustrated structure is possible without departing from the spirit and scope of the invention. Therefore it is to be understood that the invention is not limited to the precise details of construction illustrated and described.

What I claim is:

In an electric switch mechanism of the type disclosed, in combination,

a terminal assembly interpolated in a wiring circuit and permanently installed in a wall opening and the like, and a removable snap action toggle switch unit complemental thereto, said terminal assembly including:

a conventional rectangular outlet box that is open at the front, and is defined by a rear wall, top and bottom walls, and a pair of side walls, said top and bottom walls each being provided along the vertical centerline of said box with an integral inturned tab segment having a threaded opening formed therein, said side walls each having one of a pair of opposed circular openings formed therein;

a mounting strap having a channel-shaped main body portion including spaced upper and lower leg segments each merging at the front into a vertical flange, each said flange having a circular opening and a tapped hole formed therein;

a generally rectangular terminal block of non-conductive material rigidly secured to and dependently supported from the upper leg segment of the strap main body portion by means of a relatively heavy screw, said block having a pair of spaced rib formations extending upwardly therefrom to lie contiguously parallel to the side edges of said leg segment whereby to stabilize the block, having a pair of spaced rib formations depending therefrom, and having formed therein a pair of spaced cavities that extend upwardly from the bottom face of the block, each cavity including an access portion that extends rearwardly from the front face of the block;

a pair of spaced terminal contact elements each fixed in one of said cavities, said contact elements being fabricated of resilient conductive strip material each to include a hairpin-like central segment that opens forwardly in alignment with the access portion aforesaid of the cavity wherein it is fixed, and a segment that extends slightly beyond one side of the block and is tapped to receive the threaded shank of one of a pair of conventional terminal screws, said screws serving to secure the exposed ends of a pair of wires in said circuit to the contact elements after said wires had been brought through said opposed circular openings formed in the side walls of the outlet box; and

a pair of screws each extending through one of the circular openings provided therefor in the vertical flanges of the mounting strap into engagement with one of the threaded opening-s formed in the inturned tab segments of the outlet box, whereby to rigidly secure said strap and the thereby supported terminal block to said box with the channel-shaped main body of said strap and the block being disposed within said outlet box;

said complemental removable snap action toggle switch unit including:

a rectangular housing of non-conductive material that is open at the front and is defined by a rear wall, top and bottom walls, and a pair of side walls;

a pair of contact elements mounted in said top Wall, said contact elements being fabricated of resilient conductive strip material each to include a finger section that projects above the housing and a U-shaped blade section that projects into the housing, said contacts being spaced in accordance with the spacing of said cavity access portions of the terminal block;

a pair of spaced ribs depending from the bottom wall of the housing, said ribs extending from the front to the rear end of the housing with the distance between the inner surfaces of them being slightly greater than that between the side edges of the lower leg segment of the mounting strap channel-shaped main body portion aforesaid; and

manually operable toggle switch mechanism within the housing for selectively establishing and breaking a connection between said U-shaped blade sections;

the distance between the inner faces of the terminal block depending rib formations being slightly greater than the distance between the outer surfaces of the side walls of said switch unit housing, whereby during insertion of the switch unit said rib formations serve as guide means for the upper portion of the unit housing and the ribs depending from the bottom wall thereof serve as guide means for the lower portion of said housing;

the tapped holes formed in the vertical flanges aforesaid of the mounting strap being adapted to receive a pair of screws for removably securing a conventional cover plate in place.

References Cited by the Examiner UNITED STATES PATENTS 2,531,350 11/1950 Chrastina 20051 2,688,057 8/1954 Slater. 2,828,394 4/1958 Mayzik 339-122 X 2,908,743 10/ 1959 Premoshis 174-53 KATHLEEN H. CLAFFY, Primary Examiner. 

